The automatic update does not start. It’s been three days since the update was released, no notification if I do not open the program.
Program updates are spread over several days to ease server load
You can either wait till it’s offered or, manually do the installation:
https://forum.avast.com/index.php?topic=216700.msg1451035#msg1451035
If you decide to do a manual update, download the Offline Installer. 